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Mapa Geológico Da Planície Costeira Entre O Rio Saí-guaçu E a Baía De São Francisco, Litoral Norte Do Estado De Santa Catarina
| Content Provider | Semantic Scholar |
|---|---|
| Author | Angulo, Rodolfo José Souza, Maria Cristina De |
| Copyright Year | 2004 |
| Abstract | A geologia de superficie da regiao costeira, entre o Rio Sai-Guacu e a Baia de Sao Francisco, litoral norte de Santa Catarina, e constituida por rochas do embasamento cristalino Pre-Cambriano e pela cobertura sedimentar do Cenozoico. O objetivo deste trabalho e apresentar um novo mapa geologico dessa cobertura, na escala 1:50.000, com enfase na planicie costeira. Na area, foram identificadas as seguintes unidades: Fm. Mina Velha do Mioceno Inferior; coluvios, leques aluviais e depositos fluviais, do Quaternario indiferenciado; terracos costeiros do Pleistoceno Superior (120.000 anos A.P.) e do Holoceno ( GEOLOGICAL MAP OF THE COASTAL PLAIN BETWEEN THE SAI-GUACU RIVER AND SAO FRANCISCO BAY, NORTHERN COAST OF THE STATE OF SANTA CATARINA Abstract The studied area is located in the northeastern area of the State of Santa Catarina between 25o57' S and 26o14' S. The surface geology of the area is composed by rocks from the Precambrian basement and from the Cenozoic sedimentary cover. In conventional geological maps, the Cenozoic sedimentary package appears as an undifferentiated unit (e.g. Siga Jr. et al. 1993). Martin et al. (1988) presented the first map of the coastal Quaternary of the State of Santa Catarina, in 1:200,000 scale. Later, Horn Filho (1997) presented a map, in the scale 1:50,000, of the Sao Francisco do Sul region. The objective of this study is to present a new geological map, in the scale 1:50,000, of the coastal plain between the Sai-Guacu River and the Sao Francisco Bay. In the studied area the following Cenozoic age units were identified: Mina Velha Formation, probably of Lower Miocene; colluvium and alluvial fans of undifferentiated Quaternary; fluvial deposits of undifferentiated Quaternary; Upper Pleistocene coastal terraces (120,000 years B.P.); Holocene coastal terraces (< 7,000 years B.P.); Holocene paleoestuarine plains; dunes; beaches and mangroves. The distribution on the surface and subsurface and the layers of facies of the coastal deposits allow an understanding of some aspects of the geological and paleogeographical evolution of the area during the Quaternary. There are extensive Pleistocene and Holocene terraces, the presence of paleolagoons on the terrace backs and also fine lagoon sediments below the terraces makes one infer that during the Upper Pleistocene and Holocene there were transgressive barrier and regressive beach/foredune ridges in the region, similar to those described by Lessa et al. (2000) in the State of Parana. The extension of the paleoestuarine plains indicates that during the Holocene transgressive maximum there were large estuaries and lagoons. The morphology of the beach/foredune ridges provides evidence that in the Holocene spits parallel to the coast foreland that would have grown northward due to the effect of the dominant littoral drift. The growth of these spits caused the migration of the inlet of Sai-Mirim River more than 6 km northward throughout the last 5,000 years. During this migration the river eroded the internal part of these spits and the Holocene transgressive barriers. |
| File Format | PDF HTM / HTML |
| DOI | 10.5380/geo.v55i0.4280 |
| Volume Number | 55 |
| Alternate Webpage(s) | https://revistas.ufpr.br/geociencias/article/download/4280/3436 |
| Alternate Webpage(s) | https://doi.org/10.5380/geo.v55i0.4280 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
